System for extracting energy from wind and thermal gradients

ABSTRACT

An inverted funnel-shaped columnar tower ( 115 ) includes a window region ( 120 ), a heat absorbing surface ( 130 ), an air entrance ( 116 ) and exit ( 117 ). Solar energy passes through the window region and heats the heat absorbing surface. A plurality of fans ( 145 ), each connected to a generator ( 150 ), are suspended within the tower and extract energy from convectively rising air, generating electricity. A fan ( 160 ) outside the tower intercepts wind and turns an internal fan ( 145 ′) that aids the convective flow, providing a self-starting feature. A plurality of rotors ( 100 ) with wings ( 705 ) are connected in groups to generators ( 725 ) and all are arranged adjacent the tower. The rotors intercept wind energy and deliver it to the generators for conversion to electricity. The rotors include a flap ( 800 ) that predetermines the direction of rotation of the rotor, providing a second self-starting feature. The convection and wind capture functions operate independently.

BACKGROUND Prior Art

Rising fuel prices resulting from decreased fossil fuel resources andthe liabilities associated with coal and nuclear power are placingincreased emphasis on the use of clean, safe, and renewable(non-exhaustible) energy sources. Global warming provides additionalimpetus to find sources of energy that do not pollute the atmosphere.Thus numerous systems are available today that extract energy fromrenewable sources, including wind, solar, hydroelectric, geothermal,bioenergy, and ocean currents.

The following is a list of some possibly relevant prior art that showsprior-art systems that extract energy from wind and solar sources. Somereferences extract energy from wind only, others from solar only, andsome from a combination of wind and solar. The list below is dividedinto these three categories. Following this list I provide a discussionof these references.

Patent or Pub. No. Kind Code Issue or Pub. Date Patentee or ApplicantWind 385,674 B1 Jul. 3, 1888 Lockwood 1,314,232 B1 Aug. 26,1919 Wohr3,902,072 B1 Aug. 26, 1975 Quinn 3,920,354 B1 Nov. 18, 1975 Decker3,922,012 B1 Nov. 25, 1975 Herz 4,303,835 B1 Dec. 1, 1981 Bair 4,494,007B1 Jan. 15, 1985 Gaston 5,182,458 B1 Jan. 26, 1993 McConachy 6,749,399B2 Jun. 15, 2004 Heronemus 7,696,635 B2 Apr. 13, 2010 Boone 7,862,290 B2Jan. 4, 2011 Diederich 2008/0093861 A1 Apr. 24, 2008 Friesth et al.2010/0233919 A1 Sep. 16, 2010 Ersoy 2011/0070068 A1 Mar. 24, 2011Cumings et al. 2012/0091727 A1 Apr. 19, 2012 Tsitron 2012/0121379 A1 May17, 2012 Chio 2012/0175882 A1 Jul. 12, 2012 Sterling et al. Solar5,381,048 B1 Jan. 10, 1995 Baird Wind and Solar 8,210,817 B2 Jul. 3,2012 Iskrenovic 2006/0016182 A1 Jan. 26, 2006 Comandu et al.2011/0215583 A1 Sep. 8, 2011 Lee et al. 2012/0020788 A1 Jan. 26, 2012Lucy 2012/0031119 A1 Feb. 9, 2012 Ahmad et al. 2012/0049622 A1 Mar. 1,2012 Young et al.Lockwood shows a windmill comprising a plurality of orientable sailsthat are suspended between a rotatable assembly of upper and lowerspokes. The sails each pivot about a first axis. The assembly of spokesrotates about a second axis, much like two spoked wheels. A vane,resembling a weather vane, rotates independently about the second axisand orients itself so that its leading end faces into the wind. As thespoke assembly rotates about the second axis, a rack-and-pinion gearsystem connected to the vane and the sails continuously reorients thesails about the first axis with respect to the orientation of the vanein such a way as to maximize the extraction of energy from the wind bythe spoke assembly that holds the sails. Although its principle ofoperation is straightforward, this system is complex and contains manyparts.

Wohr shows a vertically-oriented windmill having a plurality of movablesails. The sails are attached to an assembly of upper and lower spokedwheels that rotate together about a central axis. Each sail is rotatablysuspended between the upper and lower spokes along one edge so that itis free to swing and rotate about that same edge. A cam arrangementlimits the range of rotation of the sail so that on one side of thespoke assembly the flat side of the sails is constrained to face theapproaching wind, while on the opposite side of the spoke assembly theflat side of the sails is parallel to the flow of the wind. Sailslocated between these two extremes assume intermediate orientations. Acam-and-spring assembly permits the sails with their flat sides facingthe wind to swing freely, thereby avoiding damage to the windmill inhigh-wind conditions. As with Lockwood, this system is complex andcontains many parts.

Quinn shows a large, vertically-oriented windmill for generatingelectricity. Upper and lower horizontally disposed circular members aresecured together and rotate on a common axis. The lower member is aplatform that is supported from below by a housing. A plurality ofvertical blades are interposed between the two members. Each bladeincludes a central pivot about which it can pivot. A weather vaneprovides wind direction information to an electronic circuit. As themembers rotate about their axis, an electronically-controlledarrangement of gears urges the vanes to pivot so that their flat sidesface the wind on one side of the platform and are perpendicular to thewind on the opposite side, extracting energy from the wind. A centralshaft is connected to a generator, producing electricity. This system iscomplex, large, and contains many parts that contribute to its centralrotating unit.

Decker shows a vertically-oriented windmill. A plurality of spokes holda plurality of flaps that are suspended at their upper edge and allowedto swing between a horizontal position and a vertical position. In thevertical position the flaps block the wind, causing the windmill toturn; in the horizontal position wind passes through between the flaps,exerting no appreciable force. This combination produces a torque aboutthe axis of the spokes, causing the windmill to rotate. The axis isconnected to a generator for the production of electricity. As with allthe previous windmills, Decker's contains a large number of parts in itsone rotating unit.

Herz shows a submersible power generator for converting the energy ofdeep ocean currents, tidal flows, river channel currents, and the liketo electricity. A plurality of impeller blades are hingedly attached toa plurality of spokes that are connected to a rotatable shaft thatdrives a generator. Each blade intercepts the water current in a firstrotational position, and trails freely in a second rotational position.In addition, when the blade is moving from the second rotationalposition to the first rotational position, the blade swings radiallyoutward against a stop, thereby imparting additional momentum to theblade as it turns. While Herz's apparatus operates in a manner similarto the windmills described above, it is designed for use under water.Its basic concept is an improvement over the large systems describedabove in that each rotating spoked part comprises a small number ofcomponents so that a plurality of spoked parts can be combined foradditional output, if desired.

Bair shows a wind powered generator that rotates about a vertical axis.A plurality of vertically disposed airfoils are each pivotable around avertical axis. An electro-mechanical system orients the airfoils tooptimally extract energy from the wind. As before, a large number ofindividual parts comprise a single rotating unit. In addition, thissystem is complex.

Gaston shows a wind machine that is similar to Wohr and Quinn. Aplurality of vertical blades are suspended between two spoked wheels. Avane senses the direction of the wind and orients the blades for optimalextraction of energy from the wind. A central shaft is connected to thespoked wheels and to a generator for generating electricity. WhileGaston's system is simpler than some of those discussed above, it isstill complex.

McConachy shows a high-altitude tower wind generating system. Aplurality of vertical, cascaded mast sections are connected byarticulated joints. A plurality of propeller-like rotors are mounted onthe mast sections. A generator is connected to each rotor. Anarrangement of guy wires ensures that the tower will remain intact inhigh-wind conditions. This system is primarily concerned with a singlemast construction that is supported by a dynamic guy wire tensioningsystem.

Heronemus shows a vertical array wind turbine comprising an array ofpropeller-like wind turbine rotors mounted on a tower which, in turn, isrotatably secured to a fixed pole. The tower rotates so that the rotorsface into the wind. The need to yaw the entire tower is a critical partof this system. A platform at the base of the tower rests on bogies,i.e., a plurality of low, sturdy carts, with pneumatic tires. Guy cablesbetween the tower and the base of the tower keep the tower upright,however the diameter of the base of the tower is determined by theoutward reach of the guy wires. When the system is exposed to the wind,the fixed pole and the base of the tower must provide a restoring torqueto counter the torque applied to the tower and rotors. The limitedoutreach of the guy cables and the torque on the tower causes most ofthe torque to occur at the base of the pole. Thus an extraordinarilystrong mount is required for the pole. The use of pneumatic tires posesan additional risk since the tires will undoubtedly require replacementover time.

Boone shows a wind turbine comprising a vertically rotating shaft and aplurality of horizontally disposed, box-shaped wind catchment vanes. Theboxes are mounted at a first end of the shaft and a generator is mountedat the other end. The boxes are oriented so that a line connecting thetop and bottom is horizontal, i.e., the box is tipped 90-degrees on itsside. At the bottom of the box is a flap. The flap pivots about its topedges, opening and closing the bottom of the box under predeterminedconditions. A flap is free to pivot upward when urged by the windstriking the outside, bottom of the box, leaving the box open to passthe wind with little resistance. When the box is oriented so that windenters its top, the flap inside is urged downward against the bottom ofthe box where it is restrained from pivoting further, thereby causingthe box to obstruct the flow of air. The asymmetry produced by an openbox on one side of the shaft and a closed box on the other side of theshaft produces a torque that causes the shaft to turn. The flaps inboxes at intermediate positions relative to the wind direction assumeintermediate positions between open and closed.

Diederich shows a fluid energy-harnessing apparatus with a plurality ofmovable wind foil vanes that move around a track. The apparatus issuitable for use in water or in air. The vanes are positioned to resistthe flow of advancing wind on one side of the track, and to pass theflow of advancing wind on the other. The resultant forces cause thevanes to move around the track. The vanes are connected to a chain drivethat turns a shaft connected to a generator. This system is complexmechanically and requires many parts.

Friesth shows a multi-turbine airflow amplifying generator. A pluralityof generating modules are affixed to a tower. Each module contains twoturbines. Each turbine employs two rotors that are coaxially aligned bya shaft connected to an in-line generator. A first rotor is contained ina proximal channel with a leading portion having decreasing radiustoward the first rotor, thereby adding to the air flow to a secondrotor. The second rotor is positioned at the leading edge of a diffuserwith radius increasing with distance from the second rotor. The modulesare rotatably mounted on the tower so that they can yaw and maximize airflow through the turbines and channels.

Ersoy shows a plurality of vertically-oriented sails attached to a rotorthat drives a generator. Each sail houses a plurality of flaps that arepivotable about their upper edge and are constrained to pivot within a90-degree range. When wind strikes a “positive” face of a sail, theflaps assume a “closed” or vertically downward position so that the windurges the sail to turn the rotor. When wind strikes a “negative” face ofa sail, the flaps assume an “open” or horizontal position, allowing thewind to pass freely therethrough. The flaps on each sail open and closeaccording to their position relative to the wind direction, thus urgingthe rotor to rotate and generate electricity.

Cumings shows a fluid turbine device comprising a rotatable verticalblade assembly with a plurality of blades that are mounted on a shaftand housed within an angularly positionable, partially open, shapedshroud. As fluid flows past the entire assembly, the shroud's shapecauses the shroud to assume a position such that the fluid flow isdiverted away from the return path of the blades as the blade assemblyrotates, thereby improving efficiency of the overall unit. The shaft isconnected to a generator for the production of electricity.

Tsitron shows an apparatus for generating electricity that includes aturbine, a generator connected to the turbine. A wind-guiding deviceincludes an inclined plane surrounded by side walls. The deviceintercepts a horizontal flow of wind and the inclined plane diverts theflow of wind upward to drive a vertically-oriented turbine at the top ofthe device.

Chio shows a tower type vertical axle windmill. A plurality of layersare stacked in an external housing with computer-controlled louvers inits exterior walls. Each layer includes a wind turbine connected to agenerator for the generation of electricity. The wind turbines comprisea plurality of arms with flaps that open or close, depending on theirposition relative to the wind in a manner similar to that of Ersoy,described above. The turbines also include a flywheel element to smoothout rotation and reduce vibration as the wind changes.

Sterling shows an injector venturi accelerated wind turbine. A venturistructure comprises a compression venturi inlet region, i.e., acylindrical region with decreasing radius at an entrance, followedaxially by a rear vacuum venturi region, i.e., a cylindrical region withincreasing radius, at its outlet. A plurality of vents in the rearvacuum venturi region admit passing air to speed the flow of air as itleaves the device. A propeller, connected to a generator, is positionedat the juncture of the compression and vacuum regions. The venturi andvent assembly speed the flow of air to the propeller for an improvementin aerodynamic efficiency that increases the amount of energy extractedfrom the wind.

The above references all teach extraction energy from the wind. Thefollowing reference teaches the harvesting of solar energy forconversion to electricity.

Baird shows a solar venturi turbine that includes an upwardly orientedventuri tube supported by a venturi support skirt. The tube includes avented, tapered thermopane glass enclosure that allows sunlight to passtherethrough and fall on a first, tapered centrifugal fan therewithin. Asecond, high-velocity fan is located above the first fan and a highpressure compressor is located above the second fan. A turbine with ashaft is located above the high pressure compressor section. The firstand second fans and the turbine are located in the neck of the venturi.The turbine's shaft is connected to an electrical generator forproducing electricity. A motor is used to start the apparatus.

The following references extract energy from both wind and sunlight.

Iskrenovic shows a dual wind-solar system comprising a wind turbinehaving a rotor with first vertically-oriented movable vanes withopenable/closeable slats for extracting energy from wind that enters theapparatus horizontally, and second, horizontally-oriented vanes forextracting energy from upwardly flowing, heated air. The rotor ismounted on a shaft that is connected to an electrical generator. Avented base member is designed to trap heat from sunlight, heating theair within and reducing its density so that convection carries the airupward where it impacts the second, horizontally-oriented set of scoops.Wind air enters the side of the apparatus, imparting energy to the firstset of scoops; thermal energy heats air in the base of the unit andsends air upward so that it imparts additional energy to the rotor via asecond set of scoops. All the air exits at the top of the apparatus.

Comandu shows a wind and solar energy collection system. A self-standingvertical structure resembles a very high chimney with a very large base.At the base is an air inlet for capturing wind. At the top of thechimney is an air outlet. Air, both ambient air and wind, is admittedthrough the air inlet at the base and expelled through an exit at thetop of the chimney by wind force and convection. A battery of electricalgenerators powered by propellers is positioned within the base in oneembodiment or the chimney in another embodiment. Air moving within thestructure causes the propellers to turn and drive the generators inorder to generate electricity. An optional bank of burners can addenergy to increase air flow at or near the base of the structure andreduce electrical output variations. An optional bank of solarcollectors contains a hydraulic fluid that is pumped through radiatorsat or near the base of the structure to further increase output. Theburners and pumps are under computer control. The base of the structureis optionally heated by sunlight, adding additional energy to theflowing air stream. A drawback of this system includes the use ofburners since they consume energy, rather than producing it.

Lee shows variations on a hybrid vertical axis energy apparatus thatharnesses multiple sources of energy including wind, solar (as in solarcells), and thermal updraft. His units can be connected together toincrease electrical output. Each unit comprises a large, cylindricalportion that rotates on an axial shaft that is connected to a generator.The top of the cylinder is domed and covered with solar cells. Theoutside surface of the cylinder is lined with vertical flashings forintercepting wind. The inner volume of the cylinder contains acorkscrew-like ducting that adds to the rotational momentum of theapparatus when thermal air currents are provided from below. A motorpowered by the solar cells is used to start the apparatus. Lee'svertical air flow path urges his entire apparatus to rotate. When windis blowing horizontally but there is no thermal updraft, Lee will beinefficient because rotation of the entire apparatus will force verticalflow of air through the corkscrew ducting, thereby wasting energy.

Lucy shows a wind energy system with structure similar to that ofCumings that is described above. In one embodiment, a teardrop-shapedhousing with front, rear, and side surfaces is rotatably supported on avertical shaft. The housing resembles a right-circular cylinder that hasbeen deformed by squeezing two opposite sides inward toward one-anotherso that the front surface narrows to a vertical line, while the rearsurface retains most of its original shape. The side surfaces formgradual contours from the front to the rear surface. Openings are cutinto the side surfaces and vertical air turbine rotors are installedtherein so that a radial portion of the rotor extends outside the sidesurface and is exposed to the wind while the remaining radial portion ofthe rotor extends inward from the side surface and is protected from thewind. Each rotor is connected to an electric generator. When wind ispresent, the narrow front surface of the teardrop-shaped housing pointsinto the wind and air passes along the side surfaces where it strikesthe exposed blades of the vertical turbines, urging them to turn.

Young shows an offshore, on-sea, compound renewable power plant thatproduces electricity by extracting energy from sunlight, wind, waves,ocean thermal gradients, and tides. A vertical axis wind power generatoris included. Further capabilities include an electrolysis-based hydrogengenerating system, a seawater desalination system, and a biomass dieselgeneration system. A plurality of marine platforms supporting apparatuswith these capabilities is envisioned. The output of all sources can becombined. While ambitious, this system suffers from the uncertainties ofwaves due to storms and the like.

Lockwood, Wohr, Quinn, Decker, Bair, Gaston, Boone, Diederich,Iskrenovic, and Ersoy all show single apparatuses, each with manycomponent parts. Failure of a single part can cause the entiregenerating apparatus to stop functioning. An alternative is to have asingle apparatus that comprises a plurality of power generating units sothat failure of one or two units will not significantly impact overallpower output of the whole apparatus.

Wind-only devices produce output only when wind is present. Solar-onlydevices produce output only when the sun shines on them with sufficientintensity. Wind and solar devices can be configured to surmount thesedifficulties, producing more output under varying conditions.

While each of the above systems may be suited for their particular use,all have one or more deficiencies as noted.

SUMMARY

I have discovered a new land-based design for a solar and wind energyextraction system that overcomes some limitations of the prior art. Nomotors, burners, or pumps are required. In one aspect an apparatuscombines a solar collection system and a wind collection system thatoperate independently. In another aspect, the solar collection system isaided by wind collection, however the two methods for extracting energyfrom wind and sun still operate independently of one-another. The windcollection system comprises a plurality of independentrotor-and-generator units so that if one unit fails, the system cancontinue to operate at near-full output. In other aspects, my wind andsolar collection systems are self-starting.

DRAWING FIGURES

FIG. 1 is a side, cut-away view of a first aspect of a first and basicpower generator.

FIG. 2 is a perspective view of a heat absorbing enhancer that can beused in to the generator of FIG. 1.

FIGS. 3 and 4 are perspective views of fans used in a first aspect ofthe system of FIG. 1.

FIG. 5 is a schematic view of a self-starting feature of one aspect ofthe system of FIG. 1.

FIG. 6 is a partial side view of a second aspect of a first embodiment.

FIG. 7 is a top view of the aspect shown in FIG. 6.

FIG. 8 is a perspective view of a grouping of rotors according to asecond aspect of the system.

FIGS. 9 to 13 show details of a self-starting aspect of the secondaspect of the second aspect.

FIG. 14 shows the first and second aspects combined.

DRAWING REFERENCE NUMERALS 100 Rotor 105 Post 110 Beam 115 FlowContainment Tower 116 Inlet 117 Outlet 120 Windowed region 125 Earth 130Salt or heat absorbent material 135 Pipe 140 Pump 145 Fan 150 Generator151 Clutch 155 Strut 160 Fan 165 Cup 170 Arm 700 Shaft 705 Wing 710 Arm715 Bearing 720 Pulley 725 Generator 726 Leads 727 Controller 728 Load730 Transmission 735 Pulley 740 Link 800 Flap 805 Pivot 810 Spring 815Stop 1000 Lines

DESCRIPTION First Aspect of First Embodiment—Apparatus for ExtractingEnergy From Sunlight—FIGS. 1 to 5

FIG. 1 is a side, cross-sectional view of a power generator or converterthat is designed to extract energy from sunlight and wind. The main partof the generator is an inverted funnel-shaped, columnar structure orflow containment tower 115. A window or transparent region 120 (thebottom portion of flow containment tower 115 as indicated by the“Window” label) is transparent and the top portion above the windowregion is opaque. Region 120 is made of a material that passes solarradiation to the inside of tower 115 and traps longer wavelengthsgenerated therein as the solar radiation is converted to heat, in awell-known fashion, known as the greenhouse effect. One or more airinlets 116 permit air from outside tower 115 to enter the region insidetower 115. An air outlet 117 at the top of tower 115 permits air toleave tower 115.

In one version of the present aspect, a layer of earth 125 beneath tower115 supports a layer 130 of heat absorbent material such as sodiumchloride (salt), dark metal filings, and the like overlaid on earth 125.Layer 130 is used to trap heat that is generated by solar radiation thatpasses through window region 120 of tower 115. Earth 125 beneath saltlayer 130 also traps and stores heat that is conducted through layer130. Layer 130 is preferably made black in color, e.g., by the additionof a black material such as carbon, so as to absorb as much as heat aspossible. Alternatively, a black layer of material such as carbon can beapplied to the top of layer 130 with a similar result. In an alternateaspect, layer 130 is omitted and earth layer 125 remains and isoptionally coated with or mixed with a dark pigment, such as carbon.

Air adjacent earth layer 125, salt layer 130, and pipe 135 are heated bysolar radiation. In response, the density of the heated air decreasesand the air rises convectively within tower 120.

A plurality of fans or turbines 145 (FIGS. 1 and 3) are connected togenerators 150 and these are secured within tower 115 in verticallyspaced positions by a plurality of struts 155. The diameter of each fan145 is predetermined to be less than but very nearly equal to the innerdiameter of tower 115 so that rising air within tower 115 urges fans 145to turn instead of merely bypassing fans 145, as described below.

An additional fan 145′ and generator 150′ are located near the top oftower 115. In this case, the shaft of generator 150′ is also connectedto an external fan 160 (FIG. 4) above tower 115. In one alternativeaspect, generator 150′ is similar to generators 150 except that itincludes a one-way clutch 151 (FIG. 5) between fan 160 and generator150′ that permits fan 145′ and the shaft of generator 150′ to rotatefaster than fan 160. This ensures that fan 160 will not cause a drag onthe rotation of fan 145′ in the event there is little or no windavailable to turn fan 160.

FIG. 2 is a perspective view of an addition to the generator of FIG. 1.The addition is a heat-absorbing enhancer pipe having a helical portionor section 135A and a return portion or section 135B. Section 135Bcontains a heat-trapping fluid, such as lightweight heat-tolerant oil,that further increases the heat-trapping capability of tower 115.Section 135A has a spiral shape that is submerged within layer 130 atthe outer portion of the spiral and rises above layer 130 at the innerportion of the spiral. Section 135B is a return path for oil from thecenter of spiral pipe 135A to the outer portion of section 135A. In oneaspect of this addition, a pump 140 (FIG. 1) circulates theheat-trapping oil through pipe section s135A and 135B. In another aspectof this addition, pump 140 is eliminated and natural convection causesthe hottest portion of the heat-trapping oil to rise to the top ofsection 135A where it cools and then returns to the lowest level ofsection 135A via section 135B (FIG. 2).

FIG. 3 is a perspective view of one of fans 145. All of fans 145 haveangled blades and are designed to turn when urged by air that movesparallel to their axis of rotation.

FIG. 4 is a perspective view of fan 160 which, as stated, is mountedatop tower 115. Fan 160 comprises a plurality of cups 165 that are eachsecured to a spoke or arm 170. Six cups 165 and arms 170 are shown, butmore or fewer can be used. Fan 160 is designed to turn when urged by airthat moves perpendicular to its axis of rotation.

The upper part of tower 115 can be made of (a) concrete, (b) a concretecomposite material containing air, fiberglass, plastic beads, and thelike, (c) metal, (d) a lightweight metal composite, or (e) a plasticcomposite or the like. Transparent bottom part or window 120 is made ofglass or a rugged plastic like polycarbonate. The bottom part of tower115 rests on earth or on a foundation, as indicated in FIG. 1. Fans 145and 160 are made from metal, plastic, and reinforced composite plasticmaterials. Generators 150 are connected to a power control unit (notshown) that combines their output and transmits it to a power grid (notshown). Pipe 135 is made of iron, steel, aluminum, or a metal alloy.

Tower 115 can be about 1 km (0.62 mile or 3281 feet) tall and hasdiameter of about 1 km at its base, although other sizes can beprovided.

First Aspect Operation—FIG. 1

During daylight hours, solar radiation passes through window portion 120and strikes layer 130, warming it. As the air near layer 130 becomeswarmer than the air further up in tower 115, convective forces will urgethe air to move upward inside tower 115. Air moving upward inside tower115 passes through the volume occupied by fans 145 and urges them torotate, in turn rotating the shafts of generators 150 and generatingelectricity.

Pipe arrangement 135 and the heat-trapping fluid absorb heat from saltlayer 130 and conduct this heat to the center of tower 115, furtherwarming the air and increasing convective forces there.

Self-Starting Feature.

FIG. 5 is a schematic side cross-sectional view of fan 160, generator150′, and fan 145. An optional clutch 151 is described above. If thesolar collecting system has lain idle in cold conditions, on a winternight for example, cold air near the interior top of tower 115 will beof sufficient density to prevent the upward convection of air withintower 115, i.e., a temperature inversion exists. This condition willprevent or at least delay the starting of upward air flow within tower115. This situation is remedied by the combination of exterior fan 160and fan 145′ at exit 117 of tower 115.

Prevailing winds urge fan 160 to rotate, in turn rotating fan 145′ sincethey share the same shaft. Fan 145′ is oriented so that as fan 160rotates, fan 145′ urges air near the top of tower 115 to leave via exit117, thereby removing the temperature inversion in the air within tower115. Free convection now occurs throughout the interior of tower 115,from bottom to top.

Energy is thus extracted from sunlight by admitting solar energy to theinterior of tower 115 through window 120. The solar energy heats layer130, pipe arrangement 135, and earth 125. As it becomes warmer, air inthe vicinity of layer 130 decreases in density compared to the airfurther up inside tower 115 and convective forces urge the air upwardpast fans 145 and out through exit 117, causing fans 145 to rotate, inturn rotating the shafts of generators 150 and generating electricity.New air is admitted through vents 116 at the bottom of tower 115,allowing the process to continue.

Second Aspect Description—Apparatus for Extracting Energy FromWind—FIGS. 6 to 12

A second aspect of the present system is also shown in cut-away, sideview of FIG. 6 and top or plan view in FIG. 7. FIG. 6 shows only oneplane of the apparatus for simplicity; it is taken at a vertical planeas indicated by the line 7-7 in FIG. 6. FIG. 7 shows a full, circulararrangement of the various components comprising the present aspect.

In the present aspect, a plurality of vertical poles or pylons 105support layers of horizontal beams 110. Rotors 100 are layered invertical groups between beams 110, as indicated in FIG. 6.

On each layer of beams 110, each layer of rotors may have 42 rotors, andeach rotor may consist of a group of three wings (described below),although larger or smaller groups can be used. These groupings are shownin FIGS. 6 and 7.

FIG. 8 is a more detailed perspective view of a grouping of three rotors100 as they are mounted on a portion of one of beams 110. Each rotorcomprises a shaft 700, a plurality of wings 705, and an arm assembly 710that is rigidly secured to shaft 700 at its center and each of wings 705at the distal end of each arm. A first rotary bearing assembly 715A isrigidly secured to beam 110. The lower end of shaft 700 is inserted intoand supported by bearing 715A. A second bearing assembly 715B is securedto another of beams 110 (not shown here for clarity) that lies directlyabove the beam 110 to which bearing 715A is secured. Bearing 715B ispositioned directly above bearing 715A. The upper end of shaft 700 isinserted into bearing 715B. Shaft 700 freely rotates in bearings 715Aand 715B. A pulley 720 is firmly secured to shaft 700 a predetermineddistance above bearing 715A and beneath the lower edge of wings 705.

An electrical generator 725 is secured to beam 110 a predetermineddistance from bearing 715A. A plurality of electrical leads 726 deliverenergy from generator 725 to a power controller 727 for furtherdistribution to an electrical load 728. A shaft (not shown) extendsupward from generator 725. A transmission assembly 730 is secured to andconcentric with the shaft of generator 725. Transmission 730 operates ina manner that equalizes the contribution of torque (discussed below)contributed from each of rotors 100A, 100B, and 100C to the shaft ofgenerator 725.

A linking element 740, such as a durable, flexible belt or chain, wrapssecurely around pulleys 720 and 735. In the case of a belt, pulleys 720and 735 are sheaves, i.e., they have a grooved rim; in the case of achain, pulleys 720 and 735 have sprockets.

Two additional rotor assemblies 100B and 100C are ganged together withrotor 100A and connected to respective pulleys that are secured totransmission 730. A triangular arrangement is shown in this example,although other arrangements can be used. Two beam sections 111 and 112extend at predetermined angles from beam 110 and support rotorassemblies 100B and 100C, respectively, in the same manner as for rotor100A.

Wings 705 are 25 m tall, with their other dimensions scaled as shown inFIG. 7. Arms 710 are of a predetermined length so that the diameter ofthe circular path of wings 705 is 45 m. Beams 110 are spaced apart 35 mvertically and rotors 100A, 100B, and 100C are spaced horizontallyapproximately 35 m from one-another. The center of each group of threerotors (100A, B, and C) is at shaft 730 of generator 725. The shafts 730of each group are separated by 35 m, as can be best seen in FIG. 6.These dimensions are representative and other dimensions can be used.

Shafts 700, arms 710, and pulleys 720 are made of a sturdy metal and mayalternatively be made of a reinforced, high-strength plastic compositesuch as that sold under the trademark Zytel, manufactured by E.I. DuPontde Nemours of wilmington, Del., USA. Wings 705, including flaps 800, canalso be made of lightweight metal or a high-strength plastic compositematerial.

Generator 725 and the capacity of power controller 727 are sizedaccording to the maximum torque and speed delivered to the shaft ofgenerator 725, via transmission 730, by rotors 100A, 100B, and 100C inhigh-wind conditions.

Second Aspect Operation—FIGS. 8 to 13

When rotors 100 are initially exposed to wind passing perpendicular tothe direction of shafts 700 there is in general no impetus for therotors to turn in any particular direction since a first of wings 705 ona rotor is facing partially into the wind, a second of wings 705 on thesame rotor is facing partially away from the wind, and the third ofwings 705 is generally perpendicular to the wind. Thus a self-startingmechanism is required to initiate rotation of rotors 100 in apredetermined direction. FIGS. 8 through 12 show one such self-startingmechanism.

Wing Detail Self-Starting Aspect—Description and Operation—FIGS. 8through 12

FIG. 8 shows a perspective view of one wing 705 with a movable flap 800.FIG. 9 shows a side view of wing 705 and flap 800. Flap 800 is sized tonest into the body of wing 705 near the trailing edge of wing 705. Theleading edge of flap 800, i.e., the right-hand end in FIG. 9, includes apivot shaft 805 that runs through flap 800 and has ends that are securedto the ends of wing 705. A torsion spring 810 surrounds pivot 805 andbears on both flap 800 and wing 705 and is arranged to urge flap 800 toan upward position as shown in FIG. 9. A stop 815 is positioned to stopthe rotation of flap 800 at an angle of about 20 degrees.

When there is no wind, spring 810 urges flap 800 to rotate to itsuppermost position about pivot 805. When wind strikes one of wings 705at its trailing edge, flap 800 and the body of wing 705 block thepassage of air past the region between them. The momentum of the movingair in this region is thus transferred to wing 705, urging it to moveforward, i.e., to the right in FIG. 9, thereby urging rotor 100 torotate. As rotor 100 rotates, the remaining two wings 705 aresequentially oriented so that their flaps 800 trap wind, eventuallycausing rotor 100 to spin at higher and higher speeds. As wing 705 movesforward, the position of flap 800 produces a drag on the forward motionof the wing. Since flap 800 is no longer used to accelerate wing 705 ina forward direction, it can now be lowered to improve the efficiency ofrotor 100 as it turns.

FIG. 10 shows a side view of wing 705 moving forward above apredetermined speed. Laminar flow of the air, i.e., flow that is layeredon the surface of wing 705, indicated by lines 1000, urges flap 800 topivot downward against wing 705, overcoming the torque exerted by spring810. The predetermined speed is determined at least by the area of flap800, the shape of wing 705, and the amount of torsion produced by spring810.

FIG. 11 is a perspective view of wing 705 moving forward at anintermediate speed with flap 800 partially lowered. FIG. 12 is aperspective view of wing 705 above the predetermined speed that causesflap 800 to fully lower into the body of wing 705.

Thus when there is no wind, rotors 100 in FIGS. 6 and 7 are stationary.At low wind speeds, flaps 800 block a part of the air flow striking theback of wing 705, thereby urging wing 705 forward (FIG. 9). As eachsubsequent wing 705 rotates into the same position, its flap blocks airflow and rotor 100 is accelerated to a predetermined speed. Above thisspeed, flaps 800 serve no purpose and in fact cause drag on the forwardmotion of wings 705. Laminar flow of air over wing 705 urges flaps 800to overcome the torque exerted by spring 810 so that flaps 800 are urgedto their full lower position within wing 705. When the wind speeddecreases and rotors 100 turn at a speed below a predetermined speed,flaps 800 again rotate to their upper position as urged by spring 810.Flaps 800 in wings 705 thereby operate to provide a self-startingfeature for rotors 100.

Description and Operation Combined First and Second Aspects—FIG. 14

FIG. 14 shows a cross-sectional, cutaway view of the first and secondaspects combined. This arrangement combines the poles and fans of FIG. 6with the tower arrangement of FIG. 1. It conserves space and combinessome structural elements for extra strength. For example, posts 105 areeither supported by tower 115 or they pass through column 115 on the wayto the ground or foundation at the bottom of the two towers. Theuppermost portions of beams 110 are coplanar with the top of column 115so that wind can freely turn fan 160. As mentioned, FIG. 7 shows theplacement of fan 160 and exit 117 of column 115 with respect to thegroupings of rotors 100.

CONCLUSIONS, RAMIFICATIONS, AND SCOPE

I have provided an improved electrical power generating system andmethod. An inverted funnel-shaped, columnar tower that extracts energyfrom sunlight is surrounded by a plurality of rotors arranged in groupsthat extract energy from wind. In one aspect, both systems areself-starting and do not rely on the application of external motivepower. A significant advantage of the combined systems is the potentialfor delivery of electrical energy over 24 hours; the two systems operateindependently of one-another. Solar-powered apparatuses deliver energyonly in strong sunlight while wind-powered apparatuses can deliver atnight or on cloudy days. The height of the wind energy capturing systemplaces rotors where winds are strong and blow throughout much of a24-hour period. The design of the wind rotors is such that they do notrequire reorientation in order to face into the wind, i.e., the wind canapproach the rotors from any direction with equal effect.

While the above description contains many specificities, these shouldnot be construed as limitations on the scope, but as exemplifications ofsome present embodiments. Many other ramifications and variations arepossible using the system and methods described. For example, rotors inthe wind-capturing aspect can be grouped in numbers other than three.Each rotor can have a dedicated generator. More or fewer fans with moreor fewer blades can be used in the solar energy capturing aspect. Thesizes of the entire assemblies as well as most parts can be made largeror smaller. The materials can be changed from those indicated and theshapes of most parts can also be modified.

Thus the scope should be determined by the appended claims and theirlegal equivalents, rather than the examples and particulars given.

The invention claimed is:
 1. A system for extracting energy from windand thermal gradients, comprising: a source of air, a source of solarenergy, a funnel-shaped columnar structure having a larger end and asmaller end and an exterior and an interior, said larger end being anentrance for air and said and said smaller end being an exit for saidair, said structure being oriented so that said smaller end forms a topand said larger end forms a bottom of said structure, a window regionextending over at least a portion of said structure and arranged toadmit said solar energy to said interior of said structure, a layer ofheat absorbing material beneath said structure arranged to receive andbe heated by said solar energy that is admitted to said interior of saidstructure, thereby heating said air adjacent to said layer of heatabsorbing material and urging said air to rise convectively within saidinterior of said structure, a plurality of fans of a first kind securedto said interior of said structure, said fans of said first kind beingoriented so that they are urged to rotate by said air that risesvertically within said interior of said structure, each of said fans ofsaid first kind having means for transferring rotary motion to anelectrical generator attached thereto, an exterior fan of a second kindsecured to said structure and located outside and adjacent said exit ofsaid structure, said exterior fan of said second kind arranged to rotatein response to wind blowing at said structure and in turn arranged totransfer said rotary motion to one of said fans of said first kind andsaid electrical generator attached thereto, thereby to cause saidgenerator and said interior fan of said first kind to rotate so thatsaid interior fan of said first kind urges said air to leave saidstructure via said exit.
 2. The system of claim 1, further including asecond layer of heat absorbing material on top of said first-named layerof heat absorbing material for receiving additional heat from said solarradiation.
 3. The system of claim 2 wherein said second layer comprisesa black material.
 4. The system of claim 1 wherein said layer of heatabsorbing material is mixed with a predetermined amount of blackmaterial in order to receive additional heat from said solar radiation.5. The system of claim 1, further including a pipe arrangement forcirculating a heat trapping fluid within said layer of heat absorbingmaterial for increasing the heat-trapping capability of said system. 6.The system of claim 5, further including a pump connected in said pipearrangement for improving circulation of said heat trapping fluid withinsaid pipe arrangement.
 7. The system of claim 5 wherein said pipearrangement is configured so that circulation of said heat trappingfluid within said pipe arrangement is urged by convection.
 8. The systemof claim 1, further including an electrical load connected to saidelectrical generator.
 9. The system of claim 1, further including aone-way clutch interposed between said exterior fan of said second kindand said one of said fans of said first kind and said generator attachedthereto so that said one-way clutch disengages when said exterior fan ofsaid second kind rotates more slowly than said interior fan of saidfirst kind.
 10. A system for extracting energy from wind and thermalgradients, comprising: an inverted funnel-shaped columnar structurecontaining a plurality of fans of a first type for extracting energyfrom convective air flow due to heating by solar radiation, each of saidfans being rotatably connected to an electrical generator for generatingelectricity, and a fan of a second type rotatably connected to one ofsaid fans of said first type for urging convection in said convectiveair flow, and a plurality of rotors arranged in layers on apost-and-beam structure located outside said inverted funnel-shapedcolumnar structure that are urged to turn in a predetermined directionby wind air flow, each of said rotors being connected to an electricalgenerator for generating electricity, whereby electrical energy isextracted when said solar radiation is present and when said wind airflow is present, and said electricity derived from said fans and saidrotors are independently obtained.
 11. The system of claim 10, furtherincluding a transmission that is operably connected to at least two ofsaid rotors so that said at least two of said rotors urge said secondkind of electrical generator to turn and generate electricity.
 12. Thesystem of claim 10, further including a power controller for receivingthe electrical output of a plurality of said generators and deliveringsaid electrical output to said electrical load.
 13. The system of claim10 wherein said inverted funnel-shaped columnar structure is made ofmaterials selected from the group consisting of concrete, a concretecomposite material, metal, a lightweight metal composite material, andplastic composite materials.
 14. The system of claim 10 wherein saidinverted funnel-shaped columnar structure further includes a transparentwindow made of materials selected from the group consisting of glass andpolycarbonate plastic.
 15. The system of claim 10 wherein said fans aremade of materials selected from the group consisting of metal, plastic,and reinforced composite plastic materials.
 16. The system of claim 10,further including a load connected to said electrical generator.